I would look first at CJ SS amps, as they are products of the same design team. I use a CJ 350 myself and it is a great amp, although not cheap. But as noted above , tubes and SS have their own sound. If it is to be a back up why not try a different flavor, I am a SS user but occasionally use a tube hybrid pre amp, it gives a different, but equally valid, take on the music.

Bel Canto eVo should be on your short list. I replaced a tube amp with an eVo. Needed more power, but did not have the budget for high-powered tube. Including both tube and SS, the eVo has turned out to be one of my favorites.

No matter what solid state amp you buy you will never be happy. Forever lurking in your mind will be 'doesn't sound tube like'. Just buy another tube amp with more power. Remember, audio is a 'mind game.

the cj mv 125 has what might be described as some veiling in frequencies exceding 3000hz, some attenuation in the treble region and a very smooth presentation, again, in the treble.

while i would not expect to replicate the response of the mv 125 i would try to get as close as possible. it may not be possible , and as has been suggested , i might not like the sound of any solid state amp in comparison to the cj.